python - 使用 Python 在新进程中执行函数

Question

有没有办法做到这一点？我在想也许使用子进程或多进程，但我不知道该怎么做？

我没有任何示例代码，因为这只是一个一般性问题。

Answer 1

http://docs.python.org/library/subprocess.html

编辑：可能，我错过了，你想要什么。好吧，我能想象你的问题。

subprocess.call(["ls","-lAd"]) # executes external program. Like system()
# Capture output. Like popen, as I remember.
subprocess.check_output(["echo", "Hello World!"]) 
os.fork() # Binding to fork()

class MyThread(threading.thread):
    def run():
        print("Hello from thread")

MyThread().start()

Answer 2

是的，
python 提供了 2 种不同的方法来执行此线程和多处理，您应该使用哪种方法取决于您执行的操作。
主要区别在于线程在同一个解释器中执行函数，而多处理启动一个新的解释器并在该解释器中运行函数。这意味着当您执行 cpu 绑定操作（例如添加大量数字）和线程用于 iobound 操作（例如输入或等待某事发生）时，通常会使用多处理。
线程示例：

from threading import Thread
import time

def fun(a):
    global myVar
    myVar = "post start" # as you can see myVar is updated and can be read by the main Thread
    time.sleep(1)
    f = input(a)
    print(f"inputed {f}")

myVar = "preThread"
t = Thread(target=fun,
           args=("plz input your message ",))
t.start() # start the thread 

print("this whil run after the thread started", myVar)
t.join() # wait for thread to finisch executing
print("this whil run after the thread ended", myVar)

输出

this whil run after the thread started post start
plz input your message k
inputed k
this whil run after the thread ended post start

如果您使用多处理库，它会启动一个新的 python 解释器并将所有值复制到其中，并且打印和输入将不起作用

from multiprocessing import Process
import time

def fun(a):
    global myVar
    myVar = "post start" # as you can see myVar is updated and can be read by the main Thread
    time.sleep(1)
    f = input(a)
    print(f"inputed {f}")

myVar = "preThread"
t = Process(target=fun,
            args=("plz input your message ",))
t.start() # start the thread 

print("this whill run after the thread started", myVar)
t.join() # wait for thread to finisch executing
print("this whill run after the thread ended", myVar)

输出：

this whill run after the thread started preThread
this whill run after the thread ended preThread

如果您想了解更多信息，请阅读
https://docs.python.org/3/library/threading.html了解线程
https://docs.python.org/3/library/multiprocessing.html了解多处理\